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<DIV>Hi,</DIV>
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<DIV>I am working with COIN-BCP for quite a while. My Branch-and-Price algorithm works fine. Now I generated 2path cuts to improve the lower bound. If no columns are added to the LP during column generation, I look for violated cuts with "generate_cuts_in_lp" and add them to the problem with "cuts_to_rows". I modified "vars_to_rows" accorrdingly to obtain the right coefficients for the new variables to obtain the correct reduced costs.</DIV>
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<DIV>However, I obtain the following error:</DIV>
<DIV>LP: Returned children to TM. Waiting for new node.</DIV>
<DIV>....BCP/src/LP/BCP_lp_msg_node_rec.cpp:67: void BCP_lp_unpack_parent(BCP_lp_prob&, BCP_buffer&, BCP_lp_node&): Assertion "p.parent->cut_set._change.empty()' failed.</DIV>
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<DIV>I tracked it down and found out that in the corresponding branch no cuts have been added, while in other branches cuts have been added.</DIV>
<DIV>It seems that these cuts are somehow present when unpacking the parent although they should not. I also checked the size of the cuts in "BCP_tm_msg_node_send.cpp" in which the size seems to be correct.</DIV>
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<DIV>Has anybody any clue what is going wrong here?</DIV>
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<DIV>Thanks for your help,</DIV>
<DIV>Andrea</DIV></BODY></HTML>